The original .357 Magnum, initially known as the Registered Magnum and sometimes known as Model 27, held six rounds in a cylinder format. Most other revolver-style pistols chambered for the .357 also hold six rounds.
There are a handful of exceptions to the usual six-round capacity. Smith & Wesson, the round's designer and first producer, also made the Model 327, which comes with an eight-shot cylinder. The Israeli arms manufacturer Desert Eagle also produces a semi-automatic version that utilizes a nine-round detachable box clip. The largest standard clip is used by the SIG Sauer P229, which features a 12-round magazine.